High pressure greasing apparatus



G. B. STAPLES HIGH PRESSURE GREASING APPARATUS Filed Jan. 26, 1931 gnou/ttor, GEORGE B. STAPLES Patented July 2, 1935 UNITED STATES ATENr ori-ics HIGH PRESSURE GREASING APPARATUS Application January 26, 1931, Serial No. 511,249

2 Claims.

This invention relates to improvements in apparatus for delivering grease under high pneumatic pressures, more particularly it relates'to a portable, automatic grease gun for lubricating heavy machine parts and automotive vehicles.

Some of the objects of this inventionarez to provide an automatic grease gun-to ieed lubrican'ts under high pressure into heavy machine parts of automotive vehicles; to provide apparatus adapted to replace the used hardened lubricant in the machine part with clean, ire-sh grease; to provide pneumatically operated apparatus for 'the quick, easy and accurate control of the quantity oi grease admitted into the machine parts; to provide portable greasingv apparatuswhich can be readily pushed about to any point where the machine part to be lubricated is situated; and vto provide apparatus for delivering a continuous supply of grease under high pressure.

. 2 With these and other objects in view the invention will be best understood from the following detailed description taken in connectionwith the accompanying drawing, in which: Y

Fig. l is a longitudinal vertical cross-sectionfof the apparatus hereinafter described and claimed.

Fig. 2 is anv enlarged View of the pressure regulating valve shown in Fig. 1. Y p A Fig. 3 is an enlarged view of the air operating valve shown in Fig. 1. Fig. 4 is an enlarged view partly in section of the valve stem of the air operating valve shown in Fig. 3.

Thepreierred form of the invention as shown in Fig. l, comprises a grease tankV orcylinder I0 provided with a hand hole plate I2 adapted to make a tight fit with the top I4' of the tank by taking up on nut I6 screwed onto pin I8 passing throughV a hand hole dog 2G on top I4 of the tank. The hand hole plate I2 is partly flanged for the l insertion of a gasket between the flange and top V plate I4 so as to make an air tight joint.

VAir is supplied to cylinder I0 through a four way connection 22 provided with a screw 24 for releasing the air pressure in the apparatuswhen the air supply has been shutoff. The connection 22 is attached to a hose 26 connecting with a source of air supply, and an opening for passage of air into the tank In. Air under a pressure of from 150 to 300 pounds per square inch,.passes through hose 26 andconnection'ZZ into the tank II) and forces a grease pad 28 downward thus discharging grease 29 from the tank I0 through an outlet 32. Pad 28 fits the interior of the tank and should be well coated with grease so that 5,5u when air under pressure is applied in the chaman air release screw 52 for the purpose of releasing air when the apparatus is nrst put in operaber of the tank I0, the air will not it into the grease.

The'tank. IE] is in communication with a high pressure grease pump 4i by means of outlet pipe nipple 32, an L 34, along pipe nipple 3S, an L 3B and afoot valve unit 40 seated at the base of grease pump fil. y The bottom of the valve unit 40 has a removable cap d2 which may be removed for ,cleaning the valve unit or for movingv the valve stem. `A cylindrical clip spring screen 44 comprising a part of the`valve unit prevents any grit in the grease "irom'passing through into the grease pump. A spring 48 and a slidably mounted valve stem provided with a valve head permit the passage oi any grease through the valve chamber into the cylinder of the grease pump 4I but prevent the now of grease in the opposite direction. The greasing apparatus is mounted on a truck 49. Y f

Thecylinder of grease pump 4 I is provided with pass through l tion. During the operation or the grease gun this screw is closed to prevent the escape of grease;

VThe high pressure grease cylinder connects directly withan air cylinder 58 and has a nut 54 retaining in positionleather cup 56 to prevent leakage of grease from the grease cylinder into the air cylinder :58. The air cylinder 58 is fitted to the upper portion of the grease cylinder by means of a threaded ange and h'eld in position by lock nut B0. Air cylinder 53 isprovided with an air release screw 62 which is opened when the apparatus is not in operation to release the air pressure therefrom.

' The high pressure grease pump includes a plunger l@ which-is adapted to be vertically reciprocatedV in cylinders il and 58. In order to reciprocate the plunger by air pressure in cylinder 5S, the plunger is provided in cylinder 58, with 40 ahead, comprising a cup l2 preferably of leather, two washers i4 and l5, all iiXed to the plunger iii with a nut 18. Cylinder 58 has a hole 59 to allow fory the escape of air from the cylinder on the down stroke of the plunger lll. Below the cupleather l2 inside the air cylinder 58 is a heavy return spring 8i] of high grade steel which drives the plunger 'm on its upward stroke during the operation of the gun. The upper' end ofV the plunger is provided with xed washers and 8l spaced at an interval from each other.

The` grease cylinder 4 I opposite the air release vscrew 52', is connected to agrease discharge and check valve 8l comprising a front half 88 and a rear half 90. The rear half 90 is connected to the grease cylinder 4| and has a small passage leading into a compartment in which is a ball and spring valve 92 for closing the passage, thereby preventing grease from owing back into the grease cylinder 4| on the upward stroke of the plunger 10. The front half 88 of the valve provides a discharge conduit for the grease to the part to be lubricated and also connects with a pressiu'e control valve 96 through a nut connection 98.

The pressure regulating valve S is provided with a valve stem |02 having a circumferential recess at about the middle of its length (Fig. 2) The circumferential recess of stem |02 is normally in alignment with the lateral passages |04 of the valve 96. In the normal operation of the apparatus the valve stem I 02 is held in the position shown in Fig. 2 by the pressure exerted by a spring |08 acting against seat |06 of valve stem |02. Valve 96 is provided with a cup leather I0 and a gland nut l2 to prevent the leakage of any air from passages |04 around the valve stem during the operation of the apparatus. A sleeve nut ||4 encloses spring |08 and screws over the top of the valve 0E. The sleeve nut is screwed down only sufiiciently to maintain a satisfactory operating pressure. The air for operating plunger 10 in chamber 58 is conducted from connection 22 by a conduit 30, the air passages |04 in control valve 96, by a conduit |05 through an operating valve unit 6B and conduit 64 into the upper portion of chamber 5S. The unit 60 has a ball and spring check valve H6, adapted to shut oil" the air supply to cylinder 58 when the ball is permitted to seat. Check` valve H6 connects directly with valve body ||8 in which is mounted a hollow valve stem |20, the movement of which is guided' by nut |22.

As shown in Fig. 4 the central hole in valve stem |20 provides a passage from the lower end of the stem to its mid-portion, where the passage connects with four radial outlets |24. When the valve stem |20 is in an elevated position, outlets |24 communicate with an air exhaust passage |26. A cup leather |28 below air passage |20 in the valve body I8 prevents air in the space around valve stem Y|20 from escaping except through the radial outlets |24. Between the guide nut |22 and the head of valve stern |20 is a` spring |30 adapted to raise the valve stem when released. Air operating valve unit 65 is operated bya trip lever |32 pivoted at |33, the lever in turn being moved from one of two positions to the other by the fixed washers 86 and 31 on plunger 10. The lever |32 is held in either of the two positions and prevented from assuming a dead center position by means of a rocker' arm |34. The arm |34 is provided with a roller |36 which is held in engagement with the beveled end of the lever |32 by means of a spring |38.

The grease under high pressure delivered through valve 81 is conducted to the element to be greased by means of a exible hose conduit |36, a, grease discharge and regulating valve |38 and a metal hose conductor |40. The grease control valve |38 comprises a ball and spring check valve |42 adapted to prevent discharge of grease through outlet conductor |40 when the valve is seated, a valve pin |44`and a pivoted operating handle |48. The handle |46 is pivoted at |48 and held to a limited movement by retaining plate |50. The valve 38 is also providedwith a, cleanout screw |52.

Assuming that the greasing apparatus is charged with grease under pressure to and including the valve |38, that the pressure in the line |33 is from 5,000 to 10,000 pounds and that no grease is being delivered through outlet |40; the ball of the check valve |42 will be seated so as to prevent discharge of grease', the valve control stem |02 of valve 90 will be elevated so that air will be prevented from flowing through conduits |04 and |06 and valve stem |20 may be in the position shown in Fig. 3. If under these conditions the grease coupler |40 is attached to an element to be greased, the greasing apparatus is set in operation by pressing down onY the lever |46 which unseats the ball of valve |42 and allows grease t0 flow out through the coupler |40 to the element to be greased. The release of grease through valve |30 reduces the pressure in line |36, valve 81, and grease pump 4|, thereby causing spring |00 to force valve stem |02 to a seated position so that air will now through the conduits |04 and |06. Air is delivered to the apparatus through the pipe 26 under a pressure from 150 to 300 pounds and under the conditions thus described passes through conduits 30, |04 and |00 through valve 55 and conduit 54 into air chamber 58 above the piston head attached to plunger 10.

The air under pressure delivered above the piston head on plunger forces the plunger downward against the grease in the cylinder of pump 4| and forces the grease out through check valve 01 and to the element being greased. As the plunger 'le reaches the limit of its downward stroke, washer 80 engages trip lever |32 and swings the pointed end thereof above the roller |30 thereby permitting spring |30 to elevate Valve stein |20. This operation permits the ball of valve I5 to be seated and thereby cuts on the air supply to the cylinder 58 and at the same time brings the openings |24 into alignment with air exhaust outlet 525 so that the air may be exhausted from chamber 58 through conduit 64, valve 00, outlets |24 and exhaust opening |25. The air in fact is forced out of chamber 53 by the action of spring 80 acting against the underside of the piston head on plunger 10.

As the plunger 10 is raised in the cylinder of pump 4|, grease from cylinder' l* is forced and drawn into the cylinder of pump 4| through valve 40. As the plunger 10 reaches the limit of its upward stroke, washer 81 engages trip lever |32 and throws it into the position shown in Fig. 3, and forces the valve stem |20 to unseat the ball valve I5, thus allowing air to again flow through conduit |08 into chamber 58. Y

This operation is continued as long as grease is being delivered through connector |40 or until the pressure in conduit |36 becomes sufficiently high to force valve stem |02 against the pressure of spring |08 thereby closing air conduit |04 which in turn stops the pumping operation.

The line pressure existing in air supply line V26 is maintained constantly above the grease pad 28 in chamber I0 and in air supply line 30 so that all that is necessary to start up the apparatus is to connect the grease conductor |40 with the bearing to be greased and press down on hand lever |46 so as to unseat the ball of valve |42; The apparatus therefore is entirely automatic.

While the drawing shows the high pressure greasing apparatus somewhat in detail, it is nevertheless a diagrammatic showing, since the apparatus elements are not drawn to scale and no attempt has been made to represent the various parts in their proper size relation to each other. Furthermore the various representations of check valves and other specific elements of the apparatus are merely examples of such equipment, andother types may be used in their place. The metal hose connector |40 may include an vordinary bayonet connector or any type of connection for attaching the connector to the bearing to be lubricated.V

Having thus described the invention in its preferred form what is claimed as new is:

1. In a high pressure greasing apparatus adapted to maintain a supply of grease at a maximum desired pressure of from 6,000 to 10,000 pounds per square inch, comprising a high pressure grease pump provided with an inlet for grease and a check valved outlet for grease at high pressure, a grease supply chamber provided with means including a conduit and a strainer therein for conducting grease from said chamber into said pump and means for positively forcing grease from said chamber through said conduit intosaid pump, said pump comprising a grease compression cylinder and a iluid pressure medium cylinder, a reciprocable plunger in said grease compression cylinder,a reciprocable piston in said i pressure medium cylinder interconnected with said plunger, means for conducting a fluid pressure medium into said pressure medium cylinder for moving said piston, said means including a supply conduit and a Valve mechanism for effecting the supply of fluid to and discharge of uid from said pressure medium cylinder, said valve mechanism being operated by a reciprocable member interconnected with said piston, a high Vpressure grease discharge conduit connected to said predetermined maximum thereby preventing the grease pressure to rise above said maximum regardless of the pressure of the iluid pressure medium supplied to the pressure medium cylinder, said cut-01T Valve and associated mechanism also being adapted to allow pressure medium to for delivering grease at substantially said maximum pressure, the combination with said grease discharge conduit and said pressure medium supply conduit of a cut-off Valve in said pressure medium supply conduit and associated mechanism connecting adapted to operate said cut-off valve in response to changes in grease pressure in said grease discharge conduit, whereby the supply of pressure medium is cut oi when the grease pressure in said grease discharge conduit reaches a predetermined maximum and pressure medium is permitted to pass to said valve mechanism through into said grease discharge V conduit said cut-off valve when the grease pressure drops slightly below said predetermined maximum upon the discharge of grease through said discharge valve.

2. In a high pressure greasing apparatus adapted to maintain a supply of grease at a maximum desired pressure of from 6,000 to 10,000 pounds per square inch in a grease dispensing conduit, including a high pressure grease pump provided with a check valved inlet for grease and a check valved outlet for grease at high pressure, and a grease supply chamber connected by a grease conduit with said pump and provided with means Vfor forcing grease therefrom into said pump, said pump comprising a grease'compression cylinder and a iluid pressure medium cylinder, a reciprocable plunger in said grease compression cylinder, a reciprocable piston in said pressure medium cylinder interconnected with said plunger, meansrfor conducting a fluid pressure medium into said pressure medium cylinder for moving said piston to thereby drive said plunger into said grease compression cylinder, said means including a supply conduit and a valve mechanism for effecting the supply of iluid to and discharge of fluid from said pressure medium cylinder, said valve mechanism being operated by a reciprocable member interconnected with said piston, a high pressure grease discharge conduit connected to said grease pump outlet and provided with a discharge valve for delivering grease at a high pressure, and a cut-off valve in said pressure medium supply conduit, said cut-oli valve including a movable member operable ln response to changes in grease pressure insaid grease discharge conduit to cut oi the supply of pressure medium by being forced across said conduit when the grease pressure insaid grease discharge conduit reaches a predetermined maximum and to permit the passage of pressure medium by being allowed to recede from across said conduit when the grease pressure drops slightly below said predetermined maximum upon the discharge of grease through said discharge valve, whereby a substantially constant supply of grease at approximately said maximum pressure is maintained in said grease discharge conduit `regardless of variations in the pressure of the pressure medium supplied to the pressure medium cylinder. Y

GEORGE BRUCE STAPLES.

CERTINCATE 0F CQRREGHQN.

mem No. mmm. my 2, 193s.

GEQRGE BRUCE STAPLES.

2 is hereby Qeried ihm ermr appears in he printed. specicaion of the above numbexe @amm requng currectifm as follows: Page T1, rst eolumn, line 34, cam i, begmimg Wih *Lhe wm "prdeermixed" strike cui; ai! to and including the wrd "to" secm @scurx'ence in iin@ 39, ami insert nsead maas@ pump out and yx-@vidad wim a discharge valve; sam@ claim, ines 51-52, for me woms "and pressure medium is prmted" 'ei thereby preventing the grease psesgura fis@ above sad; maximum regardless thee pressure of the Hud pressum mdilum suppid m ma presmire meium cyine, said cu-o vave and assecatefj mehansm also being; aapted to alow pressure medium; and that 'me said Letefs Paen sho be read Wh these corectifons therein that the same may cmorm te the record @i h@ mais@ in the Pana e.

Sgna and saled this 5th day 0f November, A, E. w35

Lese Emmer (Seal) Acting Gnmssinner o Paems. 

